Shock absorber for wheel pullers



April 18, 1950 c, 60 2,504,393

SHOCK ABSORBER FOR WHEEL PULLERS Filed Dec. 15. 1941 INVENTOR. CHESZfEI? K. 000K ATTOR Patented Apr. 18, 1950.

UNITED "STATES PATE N T F Fl-CE SHOCK ABSORBER FOR. iWHEEL .PULLERS ChesterK. Cook, Vallejo, Calif. Application December 15, 1947-, Serial No.791,880

1 Claim.

This-invention relates tofa shock absorberlfor wheel'rpullers.

.Amongstheobiects of the invention is .the;elimination of :the reaction ,shockincidental to the us of mechanical and hydraulic wheel pullers in the automotive and other servicing trade-s.

Another object is the provision of a simple, compact shock absorber adaptable to conventional practice in the removal of vehicle wheels from axles, and gears, turbine rotors, and the like, keyed or frictionally mounted upon supporting shafts.

The present disclosure will illustrate a hydraulic wheel puller for vehicle wheels, having this invention applied thereto.

The mode of operation is based upon Newtons third law of motion To every action there is always an equal reaction, or if a force acts to change the state of motion of a body, the body offers a resistance equal and directly opposite to the force. If two forces act in opposite directions, then their resultant is equal to their difference, and the direction of the resultant is the same as the direction of the greater of the two forces.

The truth of the above law is dangerously manifested in the use of conventional pullers in automotive practice, in which the puller is attached to th wheel hub, and exerts pressure against the end of the tapered axle upon which the hub is frictionally wedged. In many cases a pressure of many tons is required to unseat a hub that may be rusted on the tapered axle. When the hub lets go the pulling jack may be shot outwardly several feet, endangering the operator. The resultant reactive shock often seriously damages the axle bearings, difierential gearing and the general axle assembly. In the case of an automobile, dry mud is dislodged from the inside of the fenders, showering grit into exposed parts.

Other objects and advantages will appear as the description proceeds. In the specification and the accompanying drawings the invention is shown in its preferred form. But it is to be understood that it is not limited to this form; because it may be embodied in modifications within the spirit of the invention as defined in the claim followin the description.

In the one sheet of drawings:

Fig. 1 is a longitudinal section of a wheel puller having this invention interposed between the puller jack mounted upon the wheel hub and the threaded end of the tapered axle.

Fig. 2 is an enlarged detail in vertical section of the shock absorber or safety nut.

In detail the structure shown in Fig. 1, comprises the adapter chuck I having the flange 2, bolted as at 3, 3, to the brake drum hub 4, the disc wheel having been removed from the hub.

is internally #Ihe, hub ,4 is forced on the tapered axle 6,. by nfllllt shown, threaded on the, end "i. of .the axle and bearing against the outer end of the hub, in the usual manner.

Th shock absorber comprises the nut 8, having the flange 5 and internally threaded to screw on the threaded end i of the axle 6. The flange is provided with the spanner sockets such as H] to receive a spanner for rotatin the nut on the axle.

The nut is enclosed within the cup ll having the inturned impact flange l2 and the inturned bead [3, with the cushion It interposed between the flanges 9 and I2 within the cup Hi. This resilient cushion it is preferably composed of sponge rubber or plastic compound, adapted to impound air which absorbs the shock as the cushion is compressed, as hereinafter more fully described.

The hydraulic jack has the sleeve I 5, externally threaded into the chuck 4 at 5 and has the shoulder abutting the chuck at [6. This supports the pressure jack in the chuck I that is bolted to the hub assembly. The reduced end of the knurled body I? is adjustably threaded and telescopes within the sleeve l5. The body IT has the end cap I1, with the jack screw l3 projecting therethrough, co-axially with the low pressure chamber 19.

The piston 20 is advanced in the chamber I9 by the jack screw i8 and displaces the liquid therein through the bushing 22, against the piston 23 slidable within the high pressure cylinder 24. The piston stem 25 is guided in the plug 26, closing the end of the body I1. This stem abuts the threaded end I of the tapered axle.

The invention operates substantially as follows: The body I1 is screwed into the sleeve [5 until the piston stem 25 abuts the end 1 of the axle. Continued screwing of the body into the sleeve causes the secondary piston 23 to displace the liquid until the primary piston 20 abuts the inner end of the jack screw l 8.

When the jack screw is advanced through the cap II it displaces the liquid and forces the piston stem 25 against the end 1 of the axle until sufiicient pressure is built up in the cylinders l9 and 24 to pull the hub t off the tapered axle 6. If the hub is rusted on to the axle taper, several tons of hydraulic pressure may be exerted against the axle before the hub lets go often with a violent bang.

When the hub 4 lets go from the ax1e the outer end of the hub violently impacts the casehardened flange l2 and compresses the air impounded in the cushion I 4 against the nut flange 9. This completely eliminates the incidental shock, as previously described.

The shock absorbing nut assembly shown in Fig. 2 is equally adaptable to mechanical pullers in which the equivalent of the jack screw I8 is applied directly to the end 1 of the axle. But the hydraulic form of puller shown is preferred because of its greatereificiency and smoother operation in combination with the shock absorber above described.

Having fully described this invention and its mode of operation, what I claim and desire to secure by Letters Patent is:

A shock absorber for wheel pullers comprising an annular cup having an inturned impact flange and an inturned bead on its opposite ends respectively; a threaded nut slidable within the 15 opening of said impact flange and having an eX- ternal flange bearing against said bead within said cup and means thereon for turning said nut; and a rubber-like cushion interposed be- 4 tween said impact flange and said annular flange within said cup.

CHES'I'ER K. COOK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,964,524 McIntosh June 26, 1934 2,005,103 Moorhouse Jun 18, 1935 2,331,167 Brecht et a1. Oct. 5, 1943 FOREIGN PATENTS Number Country Date 472,569 Great Britain Sept. 27, 1937 532,394 Great Britain Jan. 23, 1941 France Oct. 13. 1941 

